1. Field
The invention is in the field of couplings to connect grooved or plain end portions of pipes, and to connect hoses, valves, pipe fittings, expansion joints, dead ends of pipes, and covers, lids, and bottoms of pressure vessels. The invention also applies to connecting structural piping or other structural members.
2. State of the Art
There are various types of mechanical couplings which employ various radial mechanical means, such as clamps and rings to secure the couplings to circumferential grooves on the ends of two pipes being connected. There are also my couplings, patented under U.S. Pat. Nos. 5,387,017, and 5,868,441, each of which employ a set of camming jaw members mounted on the coupling body around the receiving opening, where, to engage or to disengage, the coupling jaw members move toward or away from a pipe received in the body. There are other couplings shown in U.S. Pat. Nos. 5,794,988, and 6,186,560, by the inventor where expandable rings are employed to engage or to disengage the coupling. The new invented coupling is more economical to produce, and is easier than other couplings to connect plain end pipe. From here on the word pipe will encompass not only lengths of pipe, but also valves, hoses, and pipe and hose fittings where a connection is made to a pipe or other hoses or fittings.